Previously it has been known in the art to utilize multi-axis vehicle control levers, also known as “joysticks”, in the operators station of prime movers in the agricultural and construction industries for controlling various vehicle and/or implement functions. It is also known that inadvertent actuation of such a control lever poses both a significant safety hazard to the vehicle operator and others who may be in the vicinity of the vehicle, as well as a risk of damage to property. Inadvertent actuation of the controller is most likely during entrance to and/or egress from the operators station, at which time the operator is more likely to be harmed by the inadvertent actuation and less able quickly to regain control of the vehicle. The likelihood of inadvertent actuation is often further increased due to the location of the joystick. The choice of location for the joystick is frequently driven by ergonomic considerations for the seated operator. Thus, locating the joystick so as to minimize the chance of inadvertent actuation during entrance to and/or egress from the vehicle would compromise the ergonomics of the lever for the properly seated operator.
In the past, attempts to mitigate the problem of inadvertent actuation have included the use of rather stiff operating joysticks which are less susceptible to inadvertent actuation. However, the use of such joysticks likewise compromises the ergonomics for the operator due to the increased fatigue associated with manipulating the lever for extended periods of time. It has also been proposed to use mechanical or electromechanical interlocks to enable the joystick for normal operation. This solution requires that the operator depress a lever or button while gripping the joystick in order for the joystick to work. Such a system provides the operator with little freedom in gripping the joystick and causes fatigue during prolonged operation.
Accordingly, there is a clear need in the art for an ergonomic multi-axis vehicle control lever that is enabled only when the operator is gripping the lever in a manner consistent with normal operation, thus obviating the possibility of inadvertent actuation of the lever while maintaining the positive ergonomic characteristics thereof.